UV Mapping in 3DS Max

While there are many modifiers under the UV section of the modfier menu you really only need one to create a UV map for any given model.

Modifiers > UV Coordinates > Unwrap UVW

This will add the ability to edit a UVW map to the modifier stack of the currently selected object.

Be aware it is also possible to add a single unwrap modifier to multiple objects within the scene. Just have all the objects you want to add the map to selected when you add it and you will be able to see and edit the UV map of each of those objects as if they were a single object. Note how modifiers added to multiple objects appear in italic in the modifier stack window.

This is incredibly useful as you *don't* need to combine the objects first! Just keep in mind deleting the modifier from one object will *not* delete it from the other selected objects.

The UV Map window interface

To bring up the 3DS Max UV editor window simply make sure the Unwrap UVW modifier is selected and select "Open UV Editor" button from the "selections" dropdown pane.

There are quite a few buttons and commands that come with the UV editor window. Like most complex parts of the program though, we only need a select few.

  • The main uv area found in the center. You can move / pan around within this view the same as the main 3d view - by Clicking the Middle Mouse Button and dragging the mouse around. Zooming is also similar, just use the Scroll Wheel.
  • The move / rotate / scale options (see the Red Arrow in the upper left, also make note of the freeform transform tool).
  • The selection mode options (lower left).
  • The snapping option (bottom right).

At this point we just want to seperate out the geometry into individual islands. There are two approaches to sorting out the islands of a model. You can actually mix and match and do both interchangeably as needed. The first involves selecting polygons that make up an island an flattening them directly. The second involves selecting edges to define "seams".

The first is quicker but doesn't allow for a UV Group that wraps around towards itself (like a tree trunk or a shirt sleeve). The second option requires a little more set up but will allow you to map cylindrical objects like this into one UV island instead of two.

(As usual it is best to first select and move ALL of the polygons of a mesh from their starting positions inside the editor area to outside the checkerboard area so that they will not interfere with further mapping. You'll move them back one at a time during the packing process.)

We'll look at each individually.

Seperating islands using polygons

The 1st approach involves you selecting islands by polygon instead of by edges. As outlined in the general section you want to select islands of areas that can lay flat without folding.

  1. Select all of the polygons you want to make up a *single* island.
  2. Left-Click Sometimes I accidentally combine "left" and "click" when I mean to type "Left-Click".

    I tell people to Lick a lot of icons.
    the "Quick Planar Map" icon which is found in the Unwrap UVW modifier properties and looks like this:
    This will join the selected polygons into one island. It will also center your selection in the UV Editor. Ignore this as you will be changing the position manually.
  3. Click the "Quick Peel" icon. This can also be found in the Unwrap UVW modifier properties and will attempt to flatten the island out so that none of the polygons are overlapping.

From here you should see the island you made selected within the UV Editor window. While it is still selected move it away from the main UV Map area (in any direction not already occupied) so that it is not overlapping any other polygon group. Once you've moved all the islands away you can then start moving them back in.

Seperating islands using seams

The other option to define the islands of a uv map is by selecting edges on our model to become "seams", or edges that will be split when the mesh is laid flat. This approach has the benefit of the seams being saved in memory so you don't have to re-select the polygon island should you not get it right the first time.

This process is as simple as selecting a seam mode from the "peel" panel within the Unwrap UVW modifier options. While in a seam mode (either edit seam or seam path) the selection mode changes.

  1. Select all of the polygon edges you wish to define the islands (see above) using the "Edit Seams" mode.
  2. Once done, double check to make sure all edge loops are "closed" so that that islands are completely cut off from each other.
  3. Leave "Edit Seams" mode and select all of the polygons to be laid out.
  4. Left-Click the "Reset Peel" button. This will attemp tto flatten the isalnd out so that none of the polygons are overlapping.

Here are the important points to keep in mind when using any of the seam tools from the seam group.

  • Left-click an edge to add a seam (turning the edge blue).
  • You do *not* have to hold down shift to select multiple seams.
  • Hold Alt and Left-click to remove a seam.
  • Optionally, make use of the "seam path" option (the second icon in the "Seams" group) to select entire lines of seams by clicking at the beginning and end of a line of edges. Max will automatically try and find a path between those two vertices.
  • When done you will have to click the "edit seams" button again to leave seam editing mode if you've been using it.

You'll probably be changing your selected seems later so don't spend too much time trying to make them "perfect". Remember what each line denotes.

  • Green lines show island borders.
  • Blue lines show seams defined by the user.

After defining a single island with either of these approaches you'll want to move the selected island out of the bounds of the main UV Map and leave it somewhere where it does not overlap another island.

Then it will be a simple matter of packing the islands together within the UV Map bounds as outlined in the main "texturing" section.

Editing a mapped model

IMPORTANT: Remember that just as with any other modifier, changing an "edit poly" modifier lower in the stack will affect modifiers above, usually destroying parts or all of .

If you absolutely need to add or remove polygons from a mapped model, you have two choices.

  • It *might* work to collapse the entire stack (which will preserve UVs), edit the object, and then re-add the UV modifier if needed.
  • Just add another "Edit Poly" modifier to the stack, above the uv map. And pretend the earlier "Edit Poly" modifier never existed.

When creating a uv map it is very helpful to have a checkerboard pattern ready to help judge UV island scale and any UV distortion on the model itself.

Setting the current texture to the default checkerboard is as simple as clicking the dropdown in the upper right corner of the UV Map window and selecting checkerboard. If it is already selected, don't worry, it's the actual action of selecting it *twice* that will show it on the model in 3d space.